Chadarnook is a recurring enemy in the Final Fantasy series. It appears as a demon possessing a painting.
Chadarnook appears as a boss fight in Owzer's Mansion in the World of Ruin. It is a demon possessing a painting of the esper Lakshmi. During battle, Chadarnook alternates between Goddess and Demon forms. The Demon form must be defeated to finish the battle, as the Goddess form will regenerate her HP when killed.
Chadarnook is fought during the A Lost Painting hunt in Altissia. Vyv in Lestallum requests the party to take a photo of it. It resists physical attacks but is weak to Fire. The bestiary implies that the goddess part of the ghost is the woman in the painting.